If you JUST want to read pirated ebooks? Kobo is probably the best bang for your buck. But you can also pretty easily sideload ebooks to any kindle via the email interface (which I believe Calibre can utilize).
That said? I have a mix of ebooks I got from legal and less than legal sources. And some of those legal sources include amazon kindle because the prices are REALLY good.
So I like my Onyx Boox. Yeah… it is jank as hell and it allegedly comes with a free 5g modem so be wary of what personal info you put on there. But it works well as I can use the kindle app (which also syncs with my phone) for amazon stuff and the native ereader for any epub files. And because I use a webdav to sync my notes, grabbing new books is as simple as remembering to scp
a folder to my nextcloud periodically.
Never underestimate how far Gamers will go to take away the accomplishments of a woman.
(Note: I actually have no idea who Davey Gunface is, aside from a good ass Starcraft player. This just amused me).